Dipper door latch release



Oct. 13, 1931. L. R. CULVER DIPPER DOOR LATCH RELEASE Filed July 1'7, 1929 Y J l/ v I u v m 0 1 //1 0 l m I Patented 0a. 13,1931 1 or LosfAn'qELEs, cAr rormrn m ID Mt EL A E i Appueatian nid 17,

7 My'invention" relates to azdipper door latch release and has for its principaliobjeot, the

provision jof relatively simple andsprao ti'cal fluid pressure actuated device that may '11? 5 be conveniently employed, for releasing the of a steamaorgasi-airshovel,-

Heret c-fore, ithas generally 'beenthe prac-v latch that is associated vviththe dipper: door v tice to release clipperdoor;latchesbythe c11 manual operation of a cable; chain or like flexible member and: it is one 'ofthe'jobjects of my invention toprovide'a-flui'd pressure actuated lever; "the operation of which is 1 'con trolled by a .7 foot pedal-5: and-vvhich lever when moved-under the influence'of fluid pres- 'sure, will exert pull uponlthe flexible-memberthat leads to thedipperidoorlatch,,thereby actuating'the latter to efiect 'therelease of thedipper' door. MT

$1.7m Further objectsn o l invention are to V provide a dipper door latch releasing, appa 1 ratus' that is] capable lofbeing' conveniently located on the boom or arm of the steam or gas-air shovel, to, provide simple and eflicient' means for cushioningthee lever of the device at both ends 'of its-stroke,Iandfurtherto provide ad evi'ce of the character referred to that is strong and durable in: construe:

, tio'n, positive inoperation and very effective Lisa in performing the functions for whichitiis;

intended V With the for A I view, my invention C'OIISISt/S JILfiiQI tZHJII novel features of construction and arrangement of parts that will hereinafter-be more fully [describedai'id claimed andi-"llustrated in the" accompanying drawings, i n vvhic'h* Fig. lis' a side elevationalview of'a pertionofa stear'n'jor gas-air shovel with its boom and showing improved dipperd'oor latch release in position use thereupon.

p Fig. is a plan view" lookingiiithedirec:

' a tion indicatedby' the arrow 2 Fig.1 and" .gshovvinb' the pedalthat' isflutilized for-act mating the releasing device,

Fig. 3- is" an enlarged horizontal "section taken on th line 3+3 of Fig.

Fig. 4 isjan, enlarged horizontal scfii 5Q taken on theofFig. 1. i

1929: semi No. 378,905.

' 'LAGARYRYCIILVER, moaiaeams;eimamm, Assiemma epmic rmaa,

Fig. 5 is an enlarged vertical section;

"onthe line'55 ofFig. 1. v Referring; by'numerals to the accompany- Ling drawings Which illustrate a practical the body 01' platform of a steam or 'gas-alr embodiment'of "my invention, lOfdesignates shovel,f11 the boom or swinging arm, 12 the dipper sticks,13.the drum upon which Winds i the cable-14 that leads'to the dipper door latch, lathe Swinging bracket that Carries pulley 16o-ver Which the cable 14: passesgand which swingingbracket and pulley" are adapt- I I ed to take up the bight ofoable 14 vvhenthe latch is released; I 7

' All of the parts justdescribed .arefof-Well known construction and are utilized in standard forms of steam and gas-air shovelsnow in general'useav. i

My improved dipper door-latch release eludes an upright bracket 17, preferablycast;

metal, said'bracket having aabasc plate (18 that isfirmly secured toztheboom or'arm llf 1 by means o'f-cbolts 19, andsaid base plate be ing arranged so that the body of the'upright' bracket- 17 occupies a vertical position -slightly beyond one side of the boom or arm.

'tFformedon the upper portionsof the front and rear upright, membersofbracket 17, are bearings 20 for a piston rod 21',-:and .Which.

latterprojects forwardly into a small cyl-i y v inder 22 that is secured in any suitable mangoingrand other objects in "17.: Mounted on the forward end of this piston rod and arranged for operation'within 1ner to thewfront upright member of bracket the cylinder 22', is a: piston28. v.

A fiuid pressure supply pipe 24: leads from; u asuitablesource 'of'supply: to the forward end of cylinder 22, andloca'tedin said pipe, 7

preferably at a point immediatelyadjacent to the 'cylinder22, isfanord'inary 3 Way valve 25, andtheouter stem of Which valve carries a short arm or lever 26... s Mounted: in suitable bearings 27. on the platform 10; preferably at a point immediate ly in: frOnt O-f the stationoccupied by the operator of the shovel, is a rockshaft 28v that is actuated'by pressure that'is applieclifto a s is a flexible member 31 preferably a wire or small cable.

Pedal 29, rockshaft 28 and arms 26 and are arranged so that when the pedal is de pressed, the 3-way valve will be shifted into position whereby fluid pressure may pass thru pipe 24 into the cylinder 22 in front of the piston 23 therein, and when the 3 -way valve returns to its normal position, the steam or fluid pressure that entered the cylinder is free to exhaust thru a port in the valve hous- Seated in the lower portion of bracket 17 is a transversely disposed shaft 30 and journaled on the ends thereof are the lower ends of a pair of upright arms 31 that extend alongside and above thearcuate top member 32 of the frame 17, and secured to the upper ends of these arms is an upwardly projecting arm 33. A flexible member 34, preferably a cable, connects the upper end of arm 33 with the housing of pulley 16 that is carried by the lower end of the swinging arm 15.

Fixed on that portion of the piston rod 21 that is positioned between the bearings 20, is a block 35 and projecting outwardly from the sides thereof, thru slots 36 that are formed in the arms 31, are trunnions 37.

Formed integral with the arms 31 just above the arcuate top member 32 of the bracket are housings 38, the ends of which are spaced apart to provide openings 39 and arranged between these housings is a relative- 1y stiff coil spring 40. I

Formed integral with and projecting upwardly from the ends of the arcuate top member 32, are blocks 41 against which the ends of the spring are adapted to engage when the arms 31 are swung from one position to another. Detachably connected in any suitable manner to the rear one of the blocks 41, is the upper end of a brace 42, the lower end thereof being fastened to the top of the boom or arm 11, preferably onthe side opposite from the side on which the bracket 17 is mounted.

Connected to the lower portions of the arms 31 and to a bracket that depends from the cylmder 22,'is a retractile coil spring 43 that inormally holds the arms at the forward end oftheir travel, as illustrated in Fig. 1, and for the accommodation of this spring, an opening 44 is formed thru the forward portion of the base plate 18. 4

Under normal conditions, or while the 3- way valve is open, the parts of my improved door latch release occupy the positions as illustrated in Fig. 1, and when so positioned,

the latch to which the cable 14 is connected is.

positioned so as to retain the dipper door in closed position.

To operate the latch release, pedal 29 is de pressed, thereby rocking shaft 28 so as to pull rearwardly upon wire 31, thus shifting the 3-w ay valve into position topermit fluid pressure to pass from pipe 24 into the outer end of cylinder 22, and this fluid pressure moves piston 23 rearwardly within the cylinder. The trunnions 37 on block 35 that are carried by the piston rod, engage the arms 31 and swing the same rearwardly against the resistance offered by retractile spring 43, and thus the arm 33 is swung rearwardly or away from the outer end of the boom with the result that arm or bracket 15 will be swung upon its pivot, thereby exerting pull on the cable 14 and withdrawing the dipper door latch from its keeper so as to permit the door to open.

The 3-way valve 25 is provided with a spring that acts to return the valve to its normal open position when pressure on the pedal 29 is released, and when such action takes place, the fluid pressure previously admitted to the cylinder 22 in front of piston 23 is permitted to exhaust thru the 3way valve and under the influence of retractile spring 43, the arms 31 and arm 33 will be returned to their normal forward positions, and thusthe parts of the releasing device will be set or positioned for a subsequent releasing operation.

its the arms 31 swing from one position to another, the ends of the spring 40 will contact with the blocks 41, thereby serving to cushion the arms at the ends of their travel, and which cushioning effect eliminates pounding and undue vibration.

Thus, it will be seen that I have provided a dipper door latch that is relatively simple in construction, capable of being installed and used on practically all forms of steam or gas-air shovels and which release provides efficient and convenient means for effecting and withdrawal of the latching bolt that normally retains the dipper door in closed position.

It will be understood that minor changes in the size, form and construction of the various parts of my improved dipper door latch may be made and substituted for those herein shown and described without departing from the spirit of my invention, the scope of which is set forth in the appended claims.

I claim as my invention:

1. In a dipper door latch release, a frame adapted to be positioned on the boom of a steam or gas-air shovel, an arm mounted for swinging movement on said frame, an arcuate member at the top of said frame, which arouate member is concentric with the axis of the swinging arm, a connection from said arm to the latch of the dipper door that is carried by said boom, fluid pressure actuated means for moving said arm in one direction. a spring connected to said arm for moving same in the opposite direction, and cooperating means carried by said arm and arranged on the ends of the arcuate top member of the frame for cushioning said swinging arm at both ends of its swinging movement.

2. In a dipper door latch release, a frame adapted to be positioned on the boom of a 1 a spring connected to'said armfor moving steam or gas-air shovel, an arm mounted for swinging movement on said frame, an arcuate member at the top of said frame, which arcuate member is concentric with the axis of the swinging arm, a connection from said arm to the latch of the dipper door that is carried by said boom, fluid pressure actuated means for moving said arm in one direction,

same in the opposite direction, cooperating means carried by said arm and arranged on the ends of the arcuate top member of. the frame for cushioning said swinging arm at both ends of its swinging movement, and pedally actuated means for controlling said fluid pressure actuated means. v H V 3. The combination with the shovel carry-- ing boom of a steam or gas-air shove-l, of a framemounted on said boom, an arm mounted for swinging movement-onsaid frame, a connection from said arm to-the door latch of the dipper that is carried by said boom, pedally controlled fluid pressure actuated means for imparting swinging movement to said arm, a housing on the intermediate portion 5 of said swinging arm, a spring loosely arranged within said housing, and stops on the upper portion of said frame for engaging said spring at both ends of-the swinging move mentof said arm. l

, 4. In a dipper door latch release, a frame I adapted to be positioned on the boom of a steam or gas-air shovel, an arm mounted for swinging movement on said frame, a housing formed on the intermediate portion of said arm above said frame, a spring within said housing, stops on the upper portion of said frame. for engaging the ends of said spring: at the ends of the swinging'movement of said arm, a cylinder mounted on saidframe, a

, piston arranged for operation within said cylinder, which piston is connected to the swinging arm and means for admitting fluid pressure to said cylinder in front of the piston therein. 7 p

5. Ina dipper door latch release, a frame adapted to be positionedon the boom of'a steam or gas-air shovel, an'arm mounted for swinging movement on said frame, a housing formed on the intermediate portion of said arm above said frame, a spring w1th1n said housing, stops 'on the upper portion of said the ends of said spring frame for engaging side members, an arm mounted for swinging movement on said frame, a cylinder mounted on said frame, a piston arranged for operation within said cylinder, a piston rod secured to sald piston and mounted for sliding movement throughbearings in the side members i of said frame, a block mounted on said pis ton rod between the. side members ofsaid frame, a sliding pivotal. connection between saidblock and swinging arm, means for admitting fluid pressure to said cylinder front of "the piston therein, 'a spring for restoring said arm to its normal positionv after movement by the fluid pressure actuated pis ton, and means for cushioning said arm at both ends of its swinging movement.

In testimony whereof I affix my signature.

LAGAR R. CULVERQ at the ends of the swinging movement of said arm, a cylinder mounted on said frame, a piston arranged for operatlon w1th1n said cylinder, which piston is connected to the swinging arm, means for admitting fluid pressure to said cylinder in front of the piston therein, and a spring forrestoring said arm to its normal-position after movement by the fluid pressure actuated piston.

6. In a dipper door latch release, a frame adapted to be'positioned on the boom of a steam or gas-air shovel, said frame having 

